Quarterly report pursuant to Section 13 or 15(d)

Debt, Net (Details)

v3.8.0.1
Debt, Net (Details)
 3 Months Ended 9 Months Ended
May 01, 2017
USD ($)
Sep. 30, 2017
USD ($)
extension
Sep. 30, 2016
USD ($)
Sep. 30, 2017
USD ($)
extension
Sep. 30, 2016
USD ($)
Dec. 31, 2016
USD ($)
Debt            
Carrying Value   $ 1,873,291,000   $ 1,873,291,000   $ 1,904,001,000
Deferred financing costs, net   1,419,000   1,419,000   3,128,000
Interest costs capitalized   1,100,000 $ 1,200,000 4,200,000 $ 4,300,000  
Secured Debt            
Debt            
Carrying Value   $ 164,794,000   $ 164,794,000   167,591,000
Line of Credit [Member] | Revolving Credit Facility            
Debt            
Number of extensions | extension   2   2    
Extension option period (in years)       6 months    
Loans payable            
Debt            
Deferred financing costs, net   $ 4,800,000   $ 4,800,000   6,100,000
Credit Facility [Member] | Revolving Credit Facility            
Debt            
Line of credit facility, extension fee percentage       0.075%    
Term Loan Facilities Maturing 2020            
Debt            
Repayments of long-term debt $ 200,000,000          
Fixed rate debt | Secured Debt            
Debt            
Carrying Value   151,594,000   $ 151,594,000   154,143,000
Unamortized premium included in carrying value   $ 367,000   $ 367,000   422,000
Weighted average interest rate (as a percent)   4.19%   4.19%    
Fixed rate debt | Secured Debt | Minimum            
Debt            
Stated interest rate (as a percent)   3.82%   3.82%    
Fixed rate debt | Secured Debt | Maximum            
Debt            
Stated interest rate (as a percent)   7.87%   7.87%    
Variable-rate debt            
Debt            
Description of variable rate basis       LIBOR    
Variable-rate debt | Secured Debt            
Debt            
Carrying Value   $ 13,200,000   $ 13,200,000   13,448,000
Stated interest rate (as a percent)   3.09%   3.09%    
Variable-rate debt | Secured Debt | London Interbank Offered Rate (LIBOR)            
Debt            
Variable rate, spread (as a percent)       1.85%    
Revolving Credit Facility            
Debt            
Carrying Value   $ 170,000,000   $ 170,000,000   0
Description of variable rate basis       LIBOR    
Weighted average interest rate (as a percent)   2.40%   2.40%    
Revolving Credit Facility | Minimum | London Interbank Offered Rate (LIBOR)            
Debt            
Variable rate, spread (as a percent)       0.875%    
Revolving Credit Facility | Maximum | London Interbank Offered Rate (LIBOR)            
Debt            
Variable rate, spread (as a percent)       1.60%    
Term Loan Facilities            
Debt            
Carrying Value   $ 348,371,000   $ 348,371,000   547,494,000
Description of variable rate basis       LIBOR    
Weighted average interest rate (as a percent)   2.93%   2.93%    
Aggregate additional borrowing capacity available   $ 350,000,000   $ 350,000,000    
Term Loan Facilities | Minimum | London Interbank Offered Rate (LIBOR)            
Debt            
Variable rate, spread (as a percent)       0.90%    
Term Loan Facilities | Maximum | London Interbank Offered Rate (LIBOR)            
Debt            
Variable rate, spread (as a percent)       2.40%    
3.60% Senior Notes | Unsecured senior notes            
Debt            
Carrying Value   347,445,000   $ 347,445,000   347,128,000
Debt instrument, face amount   $ 350,000,000   $ 350,000,000    
Stated interest rate (as a percent)   3.60%   3.60%    
Unamortized discount included in carrying value   $ 1,800,000   $ 1,800,000   2,000,000
Interest rate on debt (as a percent)   3.70%   3.70%    
5.250% Senior Notes | Unsecured senior notes            
Debt            
Carrying Value   $ 246,525,000   $ 246,525,000   246,176,000
Debt instrument, face amount   $ 250,000,000   $ 250,000,000    
Stated interest rate (as a percent)   5.25%   5.25%    
Unamortized discount included in carrying value   $ 3,100,000   $ 3,100,000   3,400,000
Interest rate on debt (as a percent)   5.49%   5.49%    
3.70% Senior Notes | Unsecured senior notes            
Debt            
Carrying Value   $ 298,200,000   $ 298,200,000   297,843,000
Debt instrument, face amount   $ 300,000,000   $ 300,000,000    
Stated interest rate (as a percent)   3.70%   3.70%    
Unamortized discount included in carrying value   $ 1,400,000   $ 1,400,000   1,700,000
Interest rate on debt (as a percent)   3.85%   3.85%    
5.000% Senior Notes | Unsecured senior notes            
Debt            
Carrying Value   $ 296,639,000   $ 296,639,000   296,368,000
Debt instrument, face amount   $ 300,000,000   $ 300,000,000    
Stated interest rate (as a percent)   5.00%   5.00%    
Unamortized discount included in carrying value   $ 2,800,000   $ 2,800,000   3,000,000
Interest rate on debt (as a percent)   5.15%   5.15%    
Unsecured notes payable            
Debt            
Carrying Value   $ 1,317,000   $ 1,317,000   1,401,000
Stated interest rate (as a percent)   0.00%   0.00%    
Unamortized discount included in carrying value   $ 394,000   $ 394,000   $ 460,000